School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Korea.
Exp Mol Med. 2020 May;52(5):750-761. doi: 10.1038/s12276-020-0435-8. Epub 2020 May 21.
T cell activation requires extracellular stimulatory signals that are mainly mediated by T cell receptor (TCR) complexes. The TCR recognizes antigens on major histocompatibility complex molecules with the cooperation of CD4 or CD8 coreceptors. After recognition, TCR-induced signaling cascades that propagate signals via various molecules and second messengers are induced. Consequently, many features of T cell-mediated immune responses are determined by these intracellular signaling cascades. Furthermore, differences in the magnitude of TCR signaling direct T cells toward distinct effector linages. Therefore, stringent regulation of T cell activation is crucial for T cell homeostasis and proper immune responses. Dysregulation of TCR signaling can result in anergy or autoimmunity. In this review, we summarize current knowledge on the pathways that govern how the TCR complex transmits signals into cells and the roles of effector molecules that are involved in these pathways.
T 细胞的激活需要细胞外刺激信号，这些信号主要由 T 细胞受体（TCR）复合物介导。TCR 与 CD4 或 CD8 核心受体协同作用识别主要组织相容性复合体分子上的抗原。识别后，通过各种分子和第二信使诱导 TCR 诱导的信号级联反应来传递信号。因此，T 细胞介导的免疫反应的许多特征由这些细胞内信号级联反应决定。此外，TCR 信号的强度差异将 T 细胞导向不同的效应谱系。因此，严格调控 T 细胞的激活对于 T 细胞的稳态和适当的免疫反应至关重要。TCR 信号的失调可导致失能或自身免疫。在这篇综述中，我们总结了目前关于 TCR 复合物如何将信号传入细胞的途径以及参与这些途径的效应分子的作用的知识。
